Implementation and commissioning of the phase-imaging ion-cyclotron-resonance method and mass measurements of exotic copper isotopes with ISOLTRAP

An essential component of modern nuclear physics is the description of the composition of the atomic nucleus through experimental and theoretical applications. With only two components, the protons and neutrons, it carries a lot of information which is accessible via its structure. One of these parameters, which can provide information about the structure, is the mass of the atomic nucleus, with which on the basis of the binding energy of the individual constituents, shell-closures, and thus the stability and probabilities of such structures can be explained. Among other things, this information provides the explanation on how elements such as copper, silver and gold can be formed in the first place in a double neutron star merger or in a supernova. This dissertation gives first insights into the new phase-imaging ion-cyclotron-resonance technique at ISOLTRAP, which enables an even higher resolving power of isomeric- and ground-states in a shorter measuring period than with previously used techniques. Thus, this new technique allows to measure more short-lived isotopes than before. The installation as well as the characterization in direct comparison of the old time-of-flight measurement method are evaluated. Furthermore, studies of the electron capture, of the pair $^{202}$Pb-$^{202}$Tl, are presented, with which it is shown whether they can serve the more precise upper neutrino mass limit determination. The high-precision measured masses along the neutron-rich copper isotopes $^{75-79}$Cu, which reach the neutron shell-closure $N$ = 50, are used with their nucleon structure in comparison to a calculation of a shell model to interpret the behavior of the important waiting point nuclide $^{78}$Ni. Finally, the first mass measurements of the isotopes $^{123g,m}$Cd and $^{127g,m}$Cd are presented using the phase imaging method, which were measured at ISOLTRAP and validated with existing values of other facilities. The dissertation concludes with a summary and an outlook on further improvement possibilities of the new phase imaging technique as well as a brief overview of further relevant candidates with respect to mass spectroscopy.